gcc/libgo/runtime/go-reflect-map.c

241 lines
5.3 KiB
C

/* go-reflect-map.c -- map reflection support for Go.
Copyright 2009, 2010 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include <stdlib.h>
#include <stdint.h>
#include "runtime.h"
#include "go-alloc.h"
#include "go-assert.h"
#include "go-type.h"
#include "map.h"
/* This file implements support for reflection on maps. These
functions are called from reflect/value.go. */
struct mapaccess_ret
{
uintptr_t val;
_Bool pres;
};
extern struct mapaccess_ret mapaccess (struct __go_map_type *, uintptr_t,
uintptr_t)
__asm__ (GOSYM_PREFIX "reflect.mapaccess");
struct mapaccess_ret
mapaccess (struct __go_map_type *mt, uintptr_t m, uintptr_t key_i)
{
struct __go_map *map = (struct __go_map *) m;
void *key;
const struct __go_type_descriptor *key_descriptor;
void *p;
const struct __go_type_descriptor *val_descriptor;
struct mapaccess_ret ret;
void *val;
void *pv;
__go_assert (mt->__common.__code == GO_MAP);
key_descriptor = mt->__key_type;
if (__go_is_pointer_type (key_descriptor))
key = &key_i;
else
key = (void *) key_i;
if (map == NULL)
p = NULL;
else
p = __go_map_index (map, key, 0);
val_descriptor = mt->__val_type;
if (__go_is_pointer_type (val_descriptor))
{
val = NULL;
pv = &val;
}
else
{
val = __go_alloc (val_descriptor->__size);
pv = val;
}
if (p == NULL)
ret.pres = 0;
else
{
__builtin_memcpy (pv, p, val_descriptor->__size);
ret.pres = 1;
}
ret.val = (uintptr_t) val;
return ret;
}
extern void mapassign (struct __go_map_type *, uintptr_t, uintptr_t,
uintptr_t, _Bool)
__asm__ (GOSYM_PREFIX "reflect.mapassign");
void
mapassign (struct __go_map_type *mt, uintptr_t m, uintptr_t key_i,
uintptr_t val_i, _Bool pres)
{
struct __go_map *map = (struct __go_map *) m;
const struct __go_type_descriptor *key_descriptor;
void *key;
__go_assert (mt->__common.__code == GO_MAP);
if (map == NULL)
runtime_panicstring ("assignment to entry in nil map");
key_descriptor = mt->__key_type;
if (__go_is_pointer_type (key_descriptor))
key = &key_i;
else
key = (void *) key_i;
if (!pres)
__go_map_delete (map, key);
else
{
void *p;
const struct __go_type_descriptor *val_descriptor;
void *pv;
p = __go_map_index (map, key, 1);
val_descriptor = mt->__val_type;
if (__go_is_pointer_type (val_descriptor))
pv = &val_i;
else
pv = (void *) val_i;
__builtin_memcpy (p, pv, val_descriptor->__size);
}
}
extern int32_t maplen (uintptr_t)
__asm__ (GOSYM_PREFIX "reflect.maplen");
int32_t
maplen (uintptr_t m)
{
struct __go_map *map = (struct __go_map *) m;
if (map == NULL)
return 0;
return (int32_t) map->__element_count;
}
extern unsigned char *mapiterinit (struct __go_map_type *, uintptr_t)
__asm__ (GOSYM_PREFIX "reflect.mapiterinit");
unsigned char *
mapiterinit (struct __go_map_type *mt, uintptr_t m)
{
struct __go_hash_iter *it;
__go_assert (mt->__common.__code == GO_MAP);
it = __go_alloc (sizeof (struct __go_hash_iter));
__go_mapiterinit ((struct __go_map *) m, it);
return (unsigned char *) it;
}
extern void mapiternext (unsigned char *)
__asm__ (GOSYM_PREFIX "reflect.mapiternext");
void
mapiternext (unsigned char *it)
{
__go_mapiternext ((struct __go_hash_iter *) it);
}
struct mapiterkey_ret
{
uintptr_t key;
_Bool ok;
};
extern struct mapiterkey_ret mapiterkey (unsigned char *)
__asm__ (GOSYM_PREFIX "reflect.mapiterkey");
struct mapiterkey_ret
mapiterkey (unsigned char *ita)
{
struct __go_hash_iter *it = (struct __go_hash_iter *) ita;
struct mapiterkey_ret ret;
if (it->entry == NULL)
{
ret.key = 0;
ret.ok = 0;
}
else
{
const struct __go_type_descriptor *key_descriptor;
void *key;
void *pk;
key_descriptor = it->map->__descriptor->__map_descriptor->__key_type;
if (__go_is_pointer_type (key_descriptor))
{
key = NULL;
pk = &key;
}
else
{
key = __go_alloc (key_descriptor->__size);
pk = key;
}
__go_mapiter1 (it, pk);
ret.key = (uintptr_t) key;
ret.ok = 1;
}
return ret;
}
/* Make a new map. We have to build our own map descriptor. */
extern uintptr_t makemap (const struct __go_map_type *)
__asm__ (GOSYM_PREFIX "reflect.makemap");
uintptr_t
makemap (const struct __go_map_type *t)
{
struct __go_map_descriptor *md;
unsigned int o;
const struct __go_type_descriptor *kt;
const struct __go_type_descriptor *vt;
struct __go_map* map;
void *ret;
/* FIXME: Reference count. */
md = (struct __go_map_descriptor *) __go_alloc (sizeof (*md));
md->__map_descriptor = t;
o = sizeof (void *);
kt = t->__key_type;
o = (o + kt->__field_align - 1) & ~ (kt->__field_align - 1);
md->__key_offset = o;
o += kt->__size;
vt = t->__val_type;
o = (o + vt->__field_align - 1) & ~ (vt->__field_align - 1);
md->__val_offset = o;
o += vt->__size;
o = (o + sizeof (void *) - 1) & ~ (sizeof (void *) - 1);
o = (o + kt->__field_align - 1) & ~ (kt->__field_align - 1);
o = (o + vt->__field_align - 1) & ~ (vt->__field_align - 1);
md->__entry_size = o;
map = __go_new_map (md, 0);
ret = __go_alloc (sizeof (void *));
__builtin_memcpy (ret, &map, sizeof (void *));
return (uintptr_t) ret;
}